While the CD-ROM device may be used to load software onto a computer (e.g. notebook) it may also be used to play music through that same computer's speaker(s). In recent years the popularity of playing audio files from a computer's CD-ROM drive has grown as the number of people with personal computers and notebook/laptop computers has increased dramatically.
However, in order to play music it may be necessary to have special software (e.g. Windows media player) installed on the computer to play audio files from a CD. This software has traditionally been accessed by the computer system's CPU. Therefore, it may be necessary for the computer to be powered on and booted up so that a traditional operating system using the computer's CPU can play an audio file from a computer's storage location (e.g. CD-RW, hard drive, SmartMedia, etc...). These requirements can waste time and power by requiring a system to be powered on, booted-up, and for the system to remain in this mode during the playing of audio files. “The wasting of power is a more pronounced problem in a laptop computer which is running on a battery. All laptops use some type of rechargeable battery (lithium, nickel-cadmium, nickel-metal hydride).
The battery life varies depending on the type of rechargeable battery (lithium batteries tend to hold their charge longer) and how you use your computer (frequent use of disk drives consumes a lot of battery power). In addition to the main battery, laptops have other batteries to run clocks and backup CMOS RAM. (How Stuff Works by Craig Freundenrich, Ph.D. http://howstuffworks.lycos.com/laptop.htm/printable)
Referring to FIG. 1, a diagram of a notebook computer system is illustrated. The notebook computer system of FIG. 1 includes a microprocessor (also referred to as a CPU) 104 that is coupled to several types of storage systems, such as, a read only memory (“ROM”) 109, a random access memory (“RAM”) 110, a hard drive 111 for mass storage, and a floppy disk drive 112 or drives for storage on removable magnetic floppy disks. The notebook computer system also includes a display (e.g. active matrix display) 113, manual input devices (e.g. touchpad 101, keyboard 102), and communications devices (e.g. modem) 114. To play an audio file on this notebook 100, a user would first have to make sure the notebook 100 was powered on and running. Through entries made at the touchpad 101 or keyboard 102 the user can control the playing of audio files from a CD in the notebook's disk drive 103. However, in order to accomplish this control over the CD-ROM drive 103, the user's commands must be routed through the notebook's 100 CPU 104. In order to process the command at the CPU 104, the user must have started the notebook's audio software (e.g. Windows media player). The CPU 104 using the notebook's audio software processes the user's request (e.g. play button pushed). If for example the user has pressed the play button, the following takes place. First, the CPU 104 using the notebook's audio software retrieves an audio file from the disk drive 103. Second, the CPU decompresses the file (e.g. MP3) if necessary. Next, the digital audio data is passed to the notebook's CODEC (e.g. Intel's Audio Codec '97) 105 so that the final digital data from the disk drive 103 may be converted from a digital to analog signal. After converting digital to analog, the analog signal's strength is be increased at an amplifier 106 and sent to the notebook's speaker 107 for output as music.
Referring to FIG. 2, in the prior art there is a device 201 which would allow the playing of CD audio format files from a Notebook computer's CD-ROM 202 drive while the Notebook Computer 100 is powered off or in a power saving state such as sleep or suspend mode. The prior art system 200 includes the prior art device 201, a CD-ROM Drive 202, and Equalizer 203, a Mixer 204, an AMP 205, an Audio Chip 206, and a CODEC 207. The device 201 is limited to a single format and this device 201 is not upgradeable or programmable. Such a device does not play the audio. The device 201 is limited to processing requests (e.g. from a keypad) and converting the requests to an ATAPI command. The device 201 then forwards the ATAPI command to a CD-ROM. The CD-ROM is capable of understanding ATAPI commands. The CD-ROM actually plays the song as a result of receiving the ATAPI command from the device 201. Such a device is limited to processing requests to play audio files of CD audio format while the attached computer 100 is powered off or in a power saving state (e.g. sleep/suspend). This device 201 does not have the ability to play files of MP3, WMA, or AAC files. Moreover, this device cannot be reprogrammed through a software upgrade to play files of various audio file formats (e.g. MP3, WMA, or AAC). As stated, the device 201 only processes commands and forward those commands to a CD-ROM drive.
Referring to FIG. 3, we see a diagram of the device 201 covered in FIG. 2. We are told in the prior art that the device known as an audio interface IC 300 includes a state machine 301 as contrasted with a programmable controller. The state machine 301 connects to an SMBus interface 302, to a register block 303, to an LCD control 304, and to a clock generator 305. Also, the audio interface IC 300 includes control-button logic 306 that receives electrical signals from CD-ROM control buttons. In response to such signals, the control-button logic 306 may store data into the register block 303, or it may cause a digital volume control 307 to transmit control signals to an audio output amplifier. The audio interface IC 300 also includes a Host IDE interface 308 and an IDE-signals multiplexer 309.
What is needed is a device which does not merely pass commands through to a notebook's 100 CD-ROM drive 103 instructing it to play a CD audio file of CD audio format. A device which can read files, a device which can handle multiple formats (e.g. MP3, AAC, and WMA), and a device that is upgradeable by reprogramming the device with software upgrades is needed.
Another feature which is desirable is the ability to record voice while a computer system (e.g. laptop) 100 is powered off or in a power saving state. Currently, a computer system 100 would need to be powered on and special software controlled by the CPU 104 would be needed to handle voice recording through the system's microphone. Continuing to power the entire system when the user is merely attempting to record voice through a microphone to a disc on the system's disk drive 103 wastes valuable battery 108 power. Furthermore, requiring the computer system 100 to be powered on and to bootup is time consuming.
As stated above the computer system 100 is powered by a battery 108 with a limited life. By developing a single device which allows for the playing and recording of audio files while a computer (e.g. notebook) 100 is powered off or placed in a power saving state, a significant reduction in power use may be realized. This may increase the battery life on notebook computers. In addition to battery life, time and convenience may be achieved by such a single device solution. Finally, by developing a single device which is both upgradeable and programmable, the single device will have an increased longevity and provide a greater benefit to the user than devices similar to the device in the prior art.